Do 2 regular walls offer soundproofing?
therosehermit
| Posted in General Questions on
Do 2 regular walls offer soundproofing?
2 regular walls separated by x amount of space in between; let’s say 4 feet or more.
Personally as of now, it’s for an interior 2×8 wall, then 4 feet, then an exterior 2×4 wall.
I’m trying to limit sound from going outside the house but I don’t really want to decouple that 2×8 wall as I am already trying to plumb it.
But even is it was 2 regular 2×4 walls with a huge air space in between; wouldn’t that drastically reduce the sound from going outside and traveling very far?
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Replies
Yes, you’ll get sound reduction, it’s just that we’d probably call that four foot wide “wall” a “hallway” and not a “wall”.
Do you have an easy way to make that 2x8 wall into a staggered stud wall? That would get you a good deal of sound reduction in a lot less space. Either way, use 5/8” type X drywall and not 1/2” for best performance in terms of sound reduction. A double layer is even better. You could go up to resilient channel, but it doesn’t make as much difference when you already have a double stud wall or two separate walls.
Bill
Sound control is more about details than actual construction. You can construct this shell around the house but you still need to put in doors and windows. Unless you go crazy on laminated glass like you see in a sound studio, those will always be the weak point, so most of the soundproofing of the shell is wasted.
If you are worried about sound, I would dense pack with cellulose and use two layers of 5/8 on the inside as Bill recommends. This as good as you need using even STC rated windows and doors.
Someone here also mentioned using 1 5/8" steel studs to make a double stud wall, also with double drywall, and paying special attention to air sealing penetrations etc. As far as a gap goes, from what I remember, 1/2" is pretty good, 1" is great, past 2" there's not much point.